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Re: Interface reality check

Hi Roy,

> Thank you for your efforts.  I still don't see why the WAN compatible PHY
> should be burdened with all of these add on complexities, in addition to an
> additional ~3% of bandwidth loss.

I suppose that the reason, from the viewpoint of those who support this
option, is that the modest work to implement the "gearbox" is tiny
compared to the complexity of a complete SONET framer and HDLC FCS

In addition, the WAN portion of the Uni-Phy proposal leverages any work 
done on 64b/66b for the LAN by simply adding a SONET-like wrapper.

My perception is that the "extra burden" is likely to be very much less
than the alternative full SONET framing mechanism.  If we didn't think
this, we wouldn't have made the proposal.  We are not masochists. 

However, I understand that you may see it differently.  I am not a SONET
expert and have not seen a gate count of a SONET-style framer with
modifications for 10Gb Ethernet support.  I am simply daunted by the
exceedingly complex description and block diagram. 

If you want to convince a larger audience, I'd recommend that you
consider doing a design, or finding some information on an existing
design, and posting the comparative implementation data.  I have already
done so for a 64b/66b codec design at the last meeting. 

Best regards,
Rick Walker